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If the sum of the deviations of 50 observations from 30 is 50, then the mean of these observations is:

1. 31
2. 50
3. 51
4. 30

Correct answer: 31

Solution

The mean of the observations can be found by adding the total deviation to the reference point (30) and then dividing by the number of observations. Since the total deviation is 50, the mean is calculated as 30 + (50/50) = 31.

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